Since installing Windows 10 have hit a problem with many web pages not displaying all content in Firefox. Really basic stuff like field boxes for entering details being missing or a whole page not loading when progressing through an online order or information document.

Have tried the font size fix - & my font sizes are fine. Did read it could be a Kaspersky issue (which is possible as I have historically had occasional problems with untrusted certificate on Kosher sites when using Firefox & Kaspersky together.) Saw a fix on here for changing https scanning in Avast but did not give details for Kaspersky & I cannot find it within K myself. Using Kaspersky 2016.